Should I treat my Sjögren’s differently if I have primary vs secondary Sjögren’s?
The terms "Primary and "Secondary" were first used in the 1960s and were devised by researchers who wanted to distinguish between those Sjögren’s patients whose disease was not "complicated" by other major rheumatic or autoimmune disorders. When carrying out research, the investigators wanted to make sure they were looking at purely Sjögren’s patients and not looking at outcomes for patients who had, for example, both Sjögren’s and rheumatoid arthritis (RA). They thought that could confuse clinical trials looking at how well a specific therapy worked. As such things usually happen, though, the terms began to carry over to general clinical diagnosis and medical discussions and thought patterns, and that's where everything became complicated and not helpful for patients and not even helpful for the clinicians treating them. It didn't always make a major difference for the research, either.
So, first, what do the terms mean? "Primary" has been defined as a Sjögren’s patient who does not have another major rheumatic and/or autoimmune disease and "Secondary" as a Sjögren’s patient who does. But as you can imagine, it's not always simple or easily apparent. If a patient has another major rheumatic, autoimmune disease such as lupus, RA, scleroderma or the autoimmune disease multiple sclerosis, they would have traditionally been categorized as have "Secondary Sjögren’s." The term "Secondary" has not been applied to the prevalent autoimmune thyroid diseases, however, which are common in Sjögren’s, and so the terms are somewhat tricky.
Also, investigators have confronted a dilemma when a patient has had Sjögren’s for many years and been labeled as "Primary" and then is diagnosed with another major rheumatic and/or autoimmune disease and automatically being re-labeled as "Secondary Sjögren’s." And to complicate matters more, some clinicians have now started saying their patient has "Primary Sjögren’s” and "Secondary lupus"(for example) while others undiagnosed the patient from having "Primary Sjögren’s” and changed the diagnosis to "Secondary Sjögren’s." How confusing!
Does it really matter? NO - It certainly doesn't matter to the patient or the clinician treating a patient. It doesn't alter treatment, since treatment for these diseases is based largely on the clinical manifestations and symptoms. All patients should be treated on a case-by-case basis.
Does the label mean your disease is more or less severe? ABSOLUTELY NOT. If someone has labeled you as having "Secondary Sjögren’s," it does not mean that your Sjögren’s is less severe or secondary in importance to the other condition. It also doesn't mean that symptoms that were labeled as Sjögren’s symptoms previously are now symptoms of the other disease. Autoimmune diseases often overlap, and sometimes it's difficult to tell if a symptom is Sjögren’s or, say, lupus. In fact, Sjögren’s is the most frequent disorder that occurs in conjunction with other autoimmune and rheumatic diseases, so, again, your signs and symptoms must guide the treatment.
Does the label make a difference as to whether patients are monitored for specific complications or not? NO. Again, your management and treatment should depend on your manifestations of autoimmune disease. You might be labeled as having lupus AND Sjögren’s or rheumatoid arthritis AND Sjögren’s, and then your symptoms and diseases should be managed according to your specific case and with complications specific to each in mind.
Traditionally, it has mattered to an investigator running clinical trials, but even that is now being called into question. First, diagnosis and pigeon-holing these diseases is not always easy or an exact science. Second, investigators didn't mind if patients with RA or lupus who entered clinical trials also had Sjögren’s and thought it did not muddy the results of trying a new therapeutic. Why? Because, again, like clinical treatment, the trials were primarily targeted toward clinical manifestations - for example, joint pain, which can occur in several rheumatic diseases including Sjögren’s. While a few manifestations might be distinctive of one disease versus another, such as the joint damage that occurs only in rheumatoid arthritis, the results still were based on the manifestation.
The Sjögren’s Syndrome Foundation is trying to move the medical and scientific community away from these terms, because they usually are NOT helpful or necessary. In fact, they are most often used out of habit, and while we recognize that habits can be hard to change and it can take a long time for a majority to start using different terminology, the SSF is on a mission to accomplish this. Simply put, someone either has Sjögren’s or does not have Sjögren’s. Having another identifiable disease doesn't change the fact that the patient has Sjögren’s, and a somewhat arbitrary decision about which additional diseases and conditions might change a patient between "Primary" and "Secondary" no longer makes sense.
-Katherine Hammitt, SSF Vice President of Research
This article was first published in The Moisture Seekers, SSF's member newsletter.